<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="../react18/react.development.js"></script>
  <script src="../react18/react-dom.development.js"></script>
  <script src="../react18/babel.min.js"></script>
</head>

<body>
  <div id="app"></div>
  <script type="text/babel">

    /* class App extends React.Component{
      state = {
        count:0
      }

      render(){
        console.log("----render----");
        const {count} = this.state;
        return (
          <div>
            <button onClick={this.handle} >+</button>
            <p>{count}</p>
          </div>
        )
      }

      //事件函数
      handle = () => {
        //直接修改state不会重新调用render 不会重新渲染
        this.state.count ++;
      }
    }

    const root = ReactDOM.createRoot(document.getElementById('app'));
    root.render(<App/>) */

    class App extends React.Component{
      state = {
        count: 1
      }

      render(){
        console.log("----render----");
        const {count} = this.state;
        return(
          <div>
            <button onClick={this.handle} >+</button>
            <p>{count}</p>
          </div>
        )
      }

      //直接修改state,没用，不会重新调render，不会渲染
      handle = ()=>{
        this.state.count++
      }

    }

    const root = ReactDOM.createRoot(document.getElementById('app'))
    root.render(<App/>)





  </script>
</body>

</html>